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Warning: Although escape() is not strictly deprecated (as in "removed from the Web standards"), it is defined in Annex B of the ECMA-262 standard, whose introduction states:

… All of the language features and behaviours specified in this annex have one or more undesirable characteristics and in the absence of legacy usage would be removed from this specification. …
… Programmers should not use or assume the existence of these features and behaviours when writing new ECMAScript code. …

The escape() function computes a new string in which certain characters have been replaced by a hexadecimal escape sequence.

Note: This function was used mostly for URL queries (the part of a URL following ?)—not for escaping ordinary String literals, which use the format "\xHH". (HH are two hexadecimal digits, and the form \xHH\xHH is used for higher-plane Unicode characters.)

Escaped characters in String literals can be expanded by replacing the \x with %, then using the decodeURIComponent() function.

Syntax

escape(str)

Parameters

str

A string to be encoded.

Return value

A new string in which certain characters have been escaped.

Description

The escape function is a property of the global object. Special characters are encoded with the exception of: @*_+-./

The hexadecimal form for characters, whose code unit value is 0xFF or less, is a two-digit escape sequence: %xx. For characters with a greater code unit, the four-digit format %uxxxx is used.